Troy-Bilt TB90BC - Manual (Page 20)

MAINTENANCE AND REPAIR INSTRUCTIONS
20
6. Replace the air filter inside the air filter/muffler cover
(Fig. 37, Pg. 20).
NOTE: Operating the unit without the air filter and air
filter/muffler cover assembly, will VOID the
warranty.
Reinstalling the Air filter/Muffler Cover
1. Place the air filter/muffler cover over the back of the
carburetor and muffler. Align the screw holes.
2. Insert the four (4) screws into the holes in the air
filter/muffler cover (Fig. 36, Pg. 20) and tighten.
Do not over tighten.
5. Squeeze the filter to spread and remove excess oil
(Fig. 40).
Fig. 40
Fig. 42
SPARK ARRESTOR MAINTENANCE
1. Remove air filter/muffler cover. See Removing the
Air Filter/Muffler Cover.
2. Locate muffler front and the two (2) bolts securing it
to the engine. (Fig. 41). Remove the two (2) bolts
using a flat blade screwdriver or 5/16-inch socket or
nut driver. Pull muffler off of the engine.
3. Turn muffler over to the back side and locate the
exhaust gasket. Remove the muffler gasket from the
muffler (Fig. 41).
NOTE: If exhaust gasket is torn or damaged, replace
with a new gasket before reassembling muffler.
4. Using a small flat blade screwdriver, carefully pry up
the spark arrestor from the recessed hole (Fig. 42).
Remove spark arrestor from muffler.
5. Clean the spark arrestor with a wire brush. Replace if
damaged or unable to clean thoroughly (Fig. 42).
Fig. 41
Muffler - Front Side Muffler - Back Side
Bolts
Exhaust
Gasket
Spark
Arrestor
Muffler - Back Side
Spark
Arrestor
Flat blade
Screwdriver
Spark Arrestor
6. Reinstall the spark arrestor by pressing it into the
recessed hole on muffler's back side. Make sure it
fits tightly against the muffler and is not raised up.
7. Place exhaust gasket against muffler's back side.
Align exhaust gasket bolt holes with bolt holes in
muffler. While holding exhaust gasket in place, insert
bolts into muffler's front side. (Fig. 41).
8. Place muffler with exhaust gasket in place and bolts
inserted against the engine, aligning bolt holes.
Tighten bolts to secure muffler to the engine.
If using a torque wrench torque to:
80-90 in.•lb. (9-10.2 N•m).
WARNING: If muffler is not tightened
securely, it could fall off causing damage to
the unit and possible serious personal injury.
9. Reinstall air filter/muffler cover.
Fig. 39
4. Apply enough clean SAE 30 oil to lightly coat the
filter (Fig. 39).